Water Hardness Calculator

Your details

Ion mode computes hardness from your lab or test-strip Ca and Mg readings. Convert mode translates any hardness value between the six common scales.
Calcium ion concentration from your water test, in mg/L (= ppm by mass).
mg/L
Magnesium ion concentration from your water test, in mg/L.
mg/L
ppm / mg/L as CaCO₃Hard
141.1ppm

Standard US/EPA unit; equals mg/L of calcium carbonate equivalent

Grains per gallon8.24gpg
German degrees7.9°dH
French degrees14.11°fH
Clark degrees9.9°e
Millimoles per litre1.409mmol/L
Hardness categoryHard
Calcium contribution99.9ppm
Magnesium contribution41.2ppm
141.1 ppm
Soft<60Moderately hard60-120Hard120-180Very hard180+

Your water is hard at 141.1 ppm.

  • Your water measures 141.1 ppm (8.24 gpg), which is classified as hard.
  • Hard water causes visible limescale on taps, showerheads, and inside boilers. You may notice reduced soap lather and spots on glassware.
  • A water softener or descaling filter is worth considering, especially to protect washing machines and dishwashers.
  • Calcium contributes 71% of the hardness (99.9 ppm) and magnesium contributes 29% (41.2 ppm).

Next stepFor accurate treatment sizing, pair this reading with a full water report (alkalinity, pH, TDS) before choosing a softener capacity.

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